This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Prostrate cancer is the most common cancer diagnosed among men. Recently two studies have suggested that vitamin E and selenium intake may prevent prostate cancer. The goal of SELECT is to compare the effects (good and bad) of selenium, vitamin E, selenium plus vitamin E and placebo on the occurrence of prostate cancer. Secondary goals are to determine the effects of these supplements on the occurrence of lung and colorectal cancer and all other cancers combined. Nationwide there will be 32,400 men taking part in the study. SELECT will include men aged 55 and older (African American men my be 50 years of age and older), with a goal of 20% of those enrolled being minorites. The Wake Forest University School of Medicine clinical center will recruit 250 men over five years.